The Minnesota Legislature has allocated up to 25 million dollars per year in interest revenues from the Minnesota (MN) tobacco settlement endowments to the MN Department of Health (MDH) for tobacco-use prevention. These funds are designated for comprehensive programs at the local and state levels to reduce tobacco use by adolescents. This longitudinal study proposes to use a combination of cohort, cross-sectional, and time-series designs to measure adolescent tobacco-use patterns and tobacco- related attitudes and perceptions over time at the community and individual level. The purpose of this study is to relate implementation of programs funded by the MN tobacco prevention endowment to changes in tobacco-use behaviors and attitudes of youth within individuals, communities, and the state. This study will help to identify the most beneficial strategies and methods for local and state tobacco control programs, and to measure the overall effect of the MN tobacco prevention endowment on youth. The main outcome measures collected from telephone surveys will be tobacco-use behaviors and attitudes among adolescents, and the progression of tobacco use for individuals within cohorts; these will be aggregated at the state and local level. Measures of susceptibility to tobacco use, ever use of tobacco, frequency, quantity, duration and regularity of tobacco use, and attempts to quit using tobacco will be obtained. The natural history of tobacco-use behaviors in youth is not well understood. By collecting data every six months over three years on the youth cohort, the developmental patterns of tobacco use and the predictors of changes in these patterns will be defined more precisely. The aims of the study are to document the implementation of the comprehensive tobacco prevention and control program at the state and local level; to analyze the effects of the program over three years on adolescents age 12-18; to collaborate with MDH to integrate findings into the overall evaluation of the MN program, and to identify "best practices" for tobacco control at the local and statewide level; and to further describe and define the developmental process of transition from nonsmoker to smoker.